Last week I posted some very general stuff on annual forages, which is the first time I have done that in the last several years. I haven't recommended annuals for forage in the last couple of years simply because rising fertilizer costs had wiped out most or all of the saving associated with these forage types.
Now, as you are aware, the price of ferilizer has come down by over half which has made these types of forages very feasible and cost effective again.
Last summer, when I was able to lock in fertilizer for about $450/T, we established some non-replicated demonstration trials with BMR Forage Sorghum and Piper Sudangrass to look at cost of production, grazing performance, and cost of gain.
We also established Hybrid Pearl Millet to look at cost of production and cost per ton of hay. We did not graze the Hybrid Pearl Millet.
It is critical to first understand the BMR trait in forage sorghums before we look at this analysis. Traditionally, warm-season annual forages such as sudangrass have been extremely high yielding forages, but typically aren't that useful for grazing situations due to poor quality, poor digestibility, and lots and lots of wastage in grazing situations.
Then the sorghum hybrids were developed which generally were a little leafier, better quality and better digestibility, but comparatively, they are more useful for raw yield than forage quality.
More recently the BMR trait in sorghums has been refined to create a forage sorghum with high digestibility, high forage quality and outstanding animal performance. However, total yield of sorghums that contain the BMR trait tend to yield less than conventional varieties. But the questions still remained, how cost effective are forages that contain the BMR trait?
Well, let's take a look...
Table 1 shows the cost profile of establishing the BMR forage sorghum, the cattle performance, and the cost of the gain on the steers.
Typically you can expect a little closer to 5 tons of yield/acre on this variety of forage sorghum, but with the cool temps and untimely rainfall at Miller last summer, yield suffered a bit. But eventhough yields were down, cattle still gained 2.37 lb/day. If you compare that to the cost of production of forage, you get a cost of gain of $0.65 per pound of gain. If you are looking to put cheap gain on calves, this BMR forage sorghum will get the job done.
Now if you are more interested in cost in terms of cow feed where gain doesn't matter all that much, this demostration shows that you could put cows on this sorghum in the late summer/fall and feed them for about $0.31/head/day. Not bad!!
Table 2 shows the same demonstration and analysis only using Piper sudangrass.
The cost of production for sudangrass is amazingly cheap with a cost per ton of $11.56 and cost per AUM of $4.52. However, our demonstration shows that Piper sudangrass isn't all that effective for grazing growing steers. Even though the cost of production is really cheap, the gain on those calves was pretty poor. As I said before, sudangrass has lots of yield but pretty low forage quality and with a cost of gain for calves of $1.01 per pound of gain, sudangrass might not be the best choice for growing cattle.
Cows on the other hand are another matter altogether. When we aren't that concerned about gain, we could feed a group of cows for about $0.21/head per day. WOW! That is probabaly cheaper than grass for a lot of guys.
Table 3 shows the cost of production for a hybrid pearl millet crop in our demonstration. This analysis includes the cost of cutting and baling. Again, we didn't graze the millet so I don't have any cattle performance data for you.
But it any event, the millet yielded about 4.5 tons/acre with a cost of production of $23.88 per ton. Pretty reasonable when you consider that the average cost of producing a ton of grass hay in eastern SD runs about $70/ton!! That's a lot more than I thought it was, but that is what my database shows.
Theoretically, if you turned cows out on this hybrid pearl millet you could feed them for about $0.43/head/day.
I think these demonstrations show that these types of forages have all kinds of uses and the type of forage you should plant really depends on what you want to use it for. Some work good for hay, some for growing calves, and I think all of them are good feed stock for cows...and talk about a reasonable cost!!